The goal of the Clinical Technology Core is to perform clinical investigation at a "state-of-the-art" level. In concert with the Administrative and Biostatistics Cores, the Clinical Technology Core will play a role in selection of the studies to be performed and contribute expertise to the experimental design of selected studies. This Core will be responsible for presentation of each study to human Investigational Review Boards including study design and the development of appropriate consent forms. The Core will be involved in patient recruitment and selection making use of an extensive data base to be maintained by the BOHCRC patient recruitment and selection making use of an extensive data base to be maintained by the BOHCRC. When subjects have been recruited, personnel in this Core will perform clinical measurements, carry out treatment protocols and collect all biological samples. The Core will involve established researchers and post-doctoral students in clinical investigations within the BOHCRC to develop new clinical investigators who are highly trained in the performance of clinical trials/ investigations. The Clinical Technology Core will also provide specific commonly employed laboratory assessments including the measurement of the levels of a wide range of microorganisms in biological samples and the measurement of host antibody levels to oral microorganisms. These assessments will be carried out using checkerboard DNA-DNA hybridization or immunoblotting procedures. Members of this Core will be responsible for collection of data and data entry (under supervision of the Biostatistics Core). In addition, this Core will provide t he Clinical an Laboratory portions of interim and final reports. All segments of these investigations will be carried out while conforming to the guidelines of good clinical practice (GCP) and good laboratory practice (GLP). Initial studies will focus on dental caries and periodontal diseases because of the considerable expertise of the Core personnel in these areas. As studies in other areas are introduced, experts in those areas from one or more of the four Institutions involved in the BOHCRC will be recruited to participate. These investigators will expand and diversity the clinical expertise in the Core and permit a wider range of studies to be performed. In a similar fashion, commonly requested laboratory procedures will be introduced to the Core or "contracted out" to investigators i the BOGCRC institutions.